Method of Apparatus for Processing a Signal

1. A method of processing a signal, the method comprising: receiving broadcast signals including audio data encoded by a data coding scheme and video data ; demodulating the broadcast signals using a pilot signal in the received broadcast signals to output a broadcast stream; demultiplexing the broadcast stream into the video data and the audio data; obtaining data coding identification information indicating the data coding scheme among at least a pilot coding scheme and a differential coding scheme from the audio data, wherein the differential coding scheme includes at least one of a frequency diffrential coding scheme and a time differential coding scheme; and decoding the audio data according to the pilot coding scheme indicated by the data coding identification information and obtaining datang elements of the audio data by using a pilot reference value and one or more pilot difference values which are generated using the data elements and the pilot reference value, wherein a quantity of the pilot difference values is equal to a quantity of the data elements of a current group, the pilot reference value is a single value which applies to all of the data elements of the current group, and each pilot difference value corresponds to each data element of current group.

2. The method of claim 1 , wherein the time differential coding scheme corresponds to one of a forward time differential coding scheme and a backward time differential coding scheme.

3. The method of claim 1 , wherein the demultiplexing step further comprises obtaining entropy coding identification information; and the decoding step further comprises decoding the audio data using an entropy coding scheme indicated by the entropy coding identification information.

4. The method of claim 3 , wherein the entropy decoding scheme is one of a one-dimensional coding scheme and a multi-dimensional coding scheme and the multi-dimensional coding scheme is one of a frequency pair coding scheme and a time pair coding scheme.

5. The method of claim 1 , further comprising selecting data having highest coding efficiency as a final pilot reference value after the pilot reference value has been set to each of the plurality of the data units.

6. The method of claim 1 , wherein the broadcast stream includes an internet protocol packet which includes the audio data.

7. The method of claim 1 , wherein the identifier the data coding identification information is obtained from configuration information of an audio object included in the broadcasting transmission stream.

8. An apparatus for processing a signal, the apparatus comprising: a tuner receiving broadcast signals including audio data encoded by a data coding scheme and video data; a demodulator demodulating the broadcast signals using a pilot signal in the received broadcast signals to output broadcast stream; a demultiplexer demultiplexing the broadcast stream into the video data and the audio data; and a decoder obtaining data coding identification information indicating the data coding scheme among at least a pilot coding scheme and a differential coding scheme from the audio data, wherein the differential coding scheme includes at least one of a frequency differential coding scheme and a time differential coding scheme, decoding the audio data according to the pilot coding scheme indicated by the data coding identification information and obtaining data elements of the audio data by using a pilot reference value and one or more pilot difference values which are generated using the data elements and the pilot reference value, wherein a quantity of the pilot difference values is equal to a quantity of the data elements of a current group, the pilot reference value is a single value which applies to all of the data elements of the current group, and each pilot difference value corresponds to each data element of the current group.

9. A method of processing a signal, the method comprising: encoding audio data by a data coding scheme and data coding identification information indicating the data coding scheme among at least a pilot coding scheme and a differential coding scheme; multiplexing video data and the audio data to a broadcast signals: inserting a pilot signal to the broadcast signal; and converting the broadcast signal to a RF signal and transmitting the RF signal, wherein the pilot coding scheme encodes data elements of the audio data by using a pilot reference value and one or more pilot difference values which are generated using the data elements and the pilot reference value, and wherein a quantity of the pilot difference values is equal to a quantity of the data elements of a current group, the pilot reference value is a single which applies to all of the data elements of the current group, and each pilot difference value corresponds to each data element of the current group.

10. An apparatus for processing a signal, the apparatus comprising: an encoder encoding audio data by a data coding scheme and generating data coding identification information indicating the data coding scheme among at least a pilot coding scheme and a differential coding scheme; a multiplexer multiplexing video data and the audio data to a broadcast signals; a mapper inserting a pilot signal to the broadcast signals; and a converter converting the broadcast signal to a RF signal; and a transmitter transmitting the RF signal, wherein the pilot coding scheme encodes data elements of the audio data by using a pilot reference value and one or more pilot difference values which are generated using the data elements and the pilot reference value, and wherein a quantity of the pilot difference value is equal to a quantity of the data elements of a current group, the pilot reference value is a single value which applies to all of the data elements of the current group, and each pilot difference value corresponds to each data elements of the current group.

11. The apparatus of the claim 10 , wherein the audio data includes an internet protocol (IP) packet encapsulated by a multi-protocol encapsulation.